before

after

##

#!/usr/bin/perl

use CGI;
#my $q = CGI->new;

print CGI::header();


my $file_to_read = 'aa.html';
my $html =read_file($file_to_read); 
$html=~s/<\s*include\s+file\s*=\s*"([^"]+)"\s*>/&add_template($1)/gexi;
print $html;

sub add_template{
	use File::Slurp qw/read_file/;
	return read_file($_[0]);
}

##

##

$html =~ s//&add_template($1)/gexi

##

##

if(!-f $_[0]){
 return "Could not include template '$_[0]' because: NO  FILE"
}elsif(!-r $_[0]){
 return "Could not include template '$_[0]' because: NO ACCESS TO FILE";
}